Ich is a common zoonotic disease that most aquarium keepers end up having to deal with at some point or another during the time that they have fish. The main reason that it is so easy to run across is that it is mainly environmental—no matter where you got your fish, chances are they have been exposed to Ich at some point, and it probably exists in your tank already.
So what are the causes of an ich infestation? Ich — also known as white spot disease (lat. Ichthyophthirius multifiliis) — is an opportunistic parasitic infection that is more likely to attack fish that have an immune system suppressed by stress or other environmental factors. Ich is highly contagious but can be easily prevented through water quality control measures and quarantine.
A few different things contribute to the conditions that encourage ich outbreaks, but many of them can be prevented. Read on to find out more about ich and how to keep it out of your tanks.
What Is Ich and What Does It Look Like?
Ich is one of the most pervasive diseases in aquarium maintenance, but lucky for novice fishkeepers, it can be easily identified even by people who aren’t familiar with tropical fish.
The most apparent symptom of Ich in a tank is a fish that breaks out in a series of white spots that resemble measles or chickenpox in humans. These white spots (many people compare their appearance with grains of salt) are small lesions in the skin of the fish caused by the Ich protozoa.
Here are some of the other symptoms you can expect to run into with an Ich outbreak:
- Gasping behavior or quick breathing
- “Flashing” – quickly scraping the sides of the body against rocks, aquarium décor, or the substrate on the tank’s bottom
- Lack of appetite
The worst part about Ich is that it is highly contagious, so if you have a fish that has visible symptoms of ich, the rest of your fish have been exposed and are at significant risk for coming down with the disease as well. The biggest problem with ich is that the lesions it causes leave fish very vulnerable to secondary infections, especially if the tank’s water conditions are dirty.
Once one fish has Ich, the whole tank must be treated for it if the sick fish was in a community tank. This is one of the reasons it is emphasized that fish should remain in quarantine for at least two weeks before being added to an established tank.
Ich Is Caused by Overcrowded Environments
Ich is present in most aquariums, but it is especially prevalent in the water systems of people who hold large amounts of fish together in tanks at once in overcrowded conditions, such as wholesale breeders or retail stores that sell aquarium fish.
With the large numbers of fish crammed into small areas and the stress that is induced in the fish by that kind of unnatural environment, Ich is primed to jump to a weakened fish and then spread through the tank through close contact.
Chances are at some point or another you’ve had Ich in your tank, but under most circumstances, fish are healthy enough to fight off the infection. However, once a fish develops physical symptoms of the disease, it becomes highly contagious and can jump to healthier fish, weakening the entire tank.
Ich is common enough to be considered a nuisance by most fish keepers, and it is the most deadly fish disease encountered by a majority of people who keep fish. Therefore, it’s crucial to be able to identify the causes of Ich and prevent it before it becomes a problem. Once Ich has broken out in a tank, it can be much more difficult to eradicate than preventing the conditions that cause it in the first place.
Ich Is Caused by a Compromised Immune System
Ich is often associated with new fish in a tank because these are the fish most likely to break out with it. The stress of being moved from the breeding environment to the retail environment to the home environment can cause a wild animal’s immune system to plummet. Even though many popular aquarium fish are now raised in captivity, they are not domesticated and are still wild animals.
While a healthy fish might be exposed to small amounts of Ich in their environment and be unaffected, a fish weakened by stress is unable to fight off the infection. This is how many aquarium keepers have ended up with a spotty new fish only a day or so after adding it to their community. Then, there is a good chance you’re going to see it in other fish too.
Because fish are relatively stoic animals, novice aquarium keepers often don’t recognize signs of chronic stress in their fish to address them, leading to their entire tank having a weakened immune system as a result of poor water parameters, species incompatibility, or other problems.
This is a situation that is ripe for an outbreak if an infected fish is added into the community tank already under stress. Aside from not adding new fish directly into a community tank without observing them first, the best way to prevent an outbreak of Ich or other community diseases in the tank is to make sure that the fish are healthy enough to fight off most communal diseases on their own.
Ich Is Caused by Lack of Quarantine
If you read any kind of fish-related literature, one rule which seems kind of excessive to many novice fish keepers is the rule of keeping a quarantine tank running as well as a community tank. To people who have never kept fish before, this may sound like an extreme measure just to prevent a sick fish from being introduced to a healthy, established tank.
However, Ich is one of the reasons that quarantine is considered so crucial in fishkeeping communities. While it is as common in fish communities as flu is inhuman ones, Ich is capable of killing off an entire tank of fish because of how contagious it is.
With a quarantine tank, a new fish who begins to show signs of ich can be easily treated away from the main tank. Not only does this keep any diseases or parasites on the sick fish from transferring to the community, but there are also several other benefits of having a quarantine tank available in case of an ich outbreak:
- It gives the fish keeper a place to observe any sick or injured fish without plants or hardscape in the way. Otherwise, sick and injured fish tend to hide in the tank and are challenging to monitor.
- It gives fish a place away from the community tank to heal without being harassed or killed by healthier fish (many schooling fish will single out a weak individual).
- Ich treatment often requires the tank’s filter media to be removed, since the carbon in the filter media can make many Ich medications less effective. In a quarantine tank, this isn’t an issue since there is usually only one fish in the tank at a time which creates a light bioload. Daily partial water changes are encouraged in most quarantine situations anyway.
- One treatment for Ich is a brine solution – Brine solution added to the aquarium water since salt will kill the protozoa off. While this can be therapeutic for the sick fish, many plants and species of fish such as Corydoras catfish are very sensitive to levels of salt in the water, so adding salt to a community Freshwater Fish Tank is not always a good option.
Even if it’s just a backup ten-gallon aquarium that is left in storage until a fish gets sick or new fish are purchased, a quarantine tank can be a fish keeper’s best friend when it comes to keeping ich and other diseases out of their established aquarium. Quarantine tanks are also much cheaper to set up than primary tanks since they don’t require filtration or decoration, only aeration and perhaps a hide.
It only takes one devastating outbreak of a disease in a community tank to wipe out a fish keeper’s favorite specimens to convince them of the importance of keeping their established aquariums from being exposed to contagious diseases.
How to Prevent Ich Outbreaks
The easiest way to avoid Ich outbreaks is to prevent them in the first place. Not only is treating Ich tedious and costly but by the time you figure out that you need to treat for it, chances are you’re going to be looking at losing some of your fish. Especially for those aquarium keepers who keep more expensive tropical fish, this is not a risk worth taking.
Outside of quarantining all new fish for a few weeks to make sure they don’t come down with a case of Ich as the result of shipping stress, there are several ways you can maintain your aquarium to make sure fish are healthy enough to fight off opportunistic infections.
Here are some of the methods you can use to prevent an Ich outbreak in your tank other than setting up a quarantine for new fish:
- Make sure that fish don’t suffer from temperature fluctuations. Rapidly shifting temperatures in the tank environment as the result of heater malfunctions or sloppy water changes can stress fish out severely, since fish do not undergo sharp temperature fluctuations in the wild. The best way to prevent this is to keep a thermometer on your tank and consult it regularly to detect any problems and correct them early. Water during water changes should also be heated to the same temperature as the water in the tank.
- Make sure that good water quality is maintained. Not only do dirty neglected aquariums stress out the fish that live in them and make them more susceptible to disease by reducing their immune system strength, but they are also breeding grounds for the kinds of zoonotic organisms that cause those diseases, to begin with.
- Water quality in the aquarium can be maintained through reliable biological filtration, regular (weekly) partial water changes, and monthly water chemistry tests to check the levels of biological waste in the water. Keeping live plants in the aquarium can also help contribute to good water quality.
- Make sure that sources of environmental stress are reduced. Fish do not enjoy the vibrations from stereo equipment or loud noises from television, and more timid species can be stressed out just by too much activity near the tank or bright tank lighting. Where to place a fish tank – guide might help you determine the best spot for your fish tank. Reduce environmental stress by keeping aquarium fish on a routine with fish tank lighting (lighting guide) and feeding schedules. Be mindful of the sensitivity of individual species and make sure that the aquarium is not located in an area where they will be spooked by constant foot traffic.
- Make sure fish have access to a high-quality diet. In the wild, fish have access to a wide variety of different foods, and trying to replicate this variety in their captivity diet can help contribute to their health, observable happiness, and even coloring. Well-fed fish also have robust immune systems to fight off opportunistic diseases such as ich. The little fish food guide is to be found in the link. It is also essential to take into consideration what species of fish you have and what specific types of food they might require. Primarily herbivorous fish, such as goldfish, will not do well on a diet made for cichlids, and vice versa.
- Make sure fish in the tank are compatible with each other. Novice fish keepers are notorious for throwing together species of fish that can’t get along just because they just liked the appearance of the fish in question and didn’t consider the consequences of putting two incompatible species together. This encourages behaviors such as fighting and chasing that stress fish out and leave them more vulnerable to illness.
- Make sure the fish tank isn’t overcrowded. Not only does overcrowding stress fish out and cause the kind of conditions that set up an Ich outbreak, but it also makes the outbreak even more contagious when it does happen since the infection can pass more easily from fish to fish. As tempting as it is to cram as many fish into a tank as you can fit, it isn’t what’s best for the fish.
- Make sure sickly fish are isolated. A sick fish in a community tank can develop secondary contagious diseases on top of whatever primary illness it has, and these zoonotic diseases can then spread to healthier individuals in the tank. As soon as you notice that a fish is sick or injured, it should ideally be isolated from the community/hospital tank until it is treated.
- Make sure aquarium equipment is disinfected. Any tank, bucket, or net that holds a sick or injured fish should be sanitized before being used on a healthy fish, or separate equipment should be used for sick fish versus healthy fish. This can help prevent the spread of community diseases such as Ich or fish tuberculosis.
- Make sure the store “bag water” is not added to your community tank. Pet stores and aquarium shops are the most significant vectors for contagious disease in aquarium keeping, and any water from a retail holding tank is likely to be full of zoonotic organisms that might infect your community tank. Instead, new fish should be netted from the bag before being released into a tank, and the bag water should be discarded down the drain. This not only helps prevent the introduction of disease but also helps reduce the introduction of parasites and unwanted stowaways like bladder snails, as well.
The above methods will not only help prevent an outbreak of Ich in your aquarium, but they’ll also help prevent most fish illnesses that you’re likely to run across while running your tank. Healthy fish are also happier and more colorful than their sickly counterparts, so you’ll be seeing benefits across the board by taking proper care of your tank.
Since there are not many veterinarians who deal with tropical fish, it’s also up to the aquarium owner to be at least familiar with the concepts of medical care for their fish and the fishkeeping methods that can prevent its necessity in the first place. As the person in charge of a closed system, you’re the first and last line of defense against disease in your tanks.
In case your Tank will be overrun by such desire as Ich is, watch this video, how to deal with it.
Ich is a problem that plagues many fish breeders who keep large amounts of fish in small holding tanks. Still, with proper tank maintenance and good fishkeeping practices, home aquarium keepers shouldn’t have to deal with many Ich outbreaks throughout their hobby. Between setting up a small quarantine tank to separate new additions and keeping the tank water clean, half the battle against Ich has already been fought and won.
Ich is mostly the result of poor environment and stress, and luckily these variables are easily controlled by fish owners. With just a few preventative measures, you can make sure Ich never strikes your community tank.
Photo Courtesy: https://commons.wikimedia.org/w/index.php?curid=1010022